1. Technical Field
The invention relates generally to a method and system for producing corrugated material. More particularly, the invention relates to automatically changing a flute size during the corrugation process. Particularly, the invention relates to cutting a single-faced web using a water jet as it travels along a track and into a double backer, while simultaneously introducing another single-faced web into the double backer using an air jet, without stopping or slowing the overall corrugation process and system.
2. Background Information
Corrugated paperboard is manufactured at very fast line speeds in corrugator machines which are well known in the industry. A typical corrugator machine includes at least one single-facer line which forms a single-faced web having a plurality of flutes with a particular flute size. The typical corrugator machine further includes a double backer which applies a second liner to the single-faced web to form a corrugated material, a scoring section for applying score cuts into the corrugated material, and a cutting section to divide the corrugated material into individual pieces.
In the single-facer line, corrugated flutes are formed transversely across a first material to form a corrugated web. A liquid adhesive is then applied to the tips of these flutes and the corrugated web is advanced. After the adhesive is applied, a second material is brought into contact with the glue-coated flutes to form a laminated single-faced web. The single-faced web is then conveyed through a bridge section which accumulates the single-faced web around bridge rollers for future use as needed. After the bridge section the single-faced web passes through a glue unit where an adhesive is delivered to the exposed flute tips of the single-faced web. Thereafter, both the single-faced web and a third material is delivered into the double backer, after which the third material is applied to the exposed side of the single-faced web to form a corrugated material.
Generally, corrugated material is classified depending on the size of the flutes into A, B, C, and E flute classes, which have different heights and pitches, and which are selectively employed depending upon the desired uses. The flute size is determined by two abutting rollers which have their circumferential surfaces machined into a corrugated configuration with the first material being worked into the corrugated web. Inasmuch as these rollers are typically formed of metal which have been machined into the corrugated shape, different flute sizes require that the operator advances the first material through entirely different sets of rollers.
Many motors, sensors, and mechanical and electrical equipment must be started and brought online to begin the corrugation process. Therefore, it is extremely desirable to continuously run the corrugation machine to accomplish multiple jobs in succession. Typically, an entire batch of different jobs is run successively through the corrugation machine once the mechanical and electrical systems are online. Each job may require a different flute size corresponding to the desired finished corrugated material. While multiple single-facer lines are typically employed to provide a selection of flute sizes and single-faced webs, the corrugation process currently has to stop during a flute change sequence to insert the new single-faced web into the double backer. The process of slowing down and speeding up the corrugator machine before and after this stoppage is wholly inefficient as a significant amount of time is wasted, thereby decreasing production rates. Furthermore, the flute change sequence is currently done by hand, which represents a significant safety concern as rotating parts within the double backer are formed to continuously and forcefully pull material into the machine.
Therefore, a need exists for an improved method and system for producing corrugated material in which a user may automatically change the flute size without stopping or slowing down the overall corrugation process.